1. Field of the Invention
The present invention relates to a probe head rotation mechanism, and in particular relates to a probe head rotation mechanism capable of reducing an error in a defined position of the probe by reducing an effect on a probe of heat generated by a drive source due to changing a posture of the probe.
2. Description of Related Art
Conventionally, a probe head rotation mechanism has been used, such as that disclosed in Japanese Unexamined Patent Publication No. H03-504278, which modifies a posture of a probe of a computer numerical control (CNC) coordinate measurement device. The probe head rotation mechanism is arranged between a spindle and the probe in the coordinate measurement device and is capable of tilting the probe with respect to an axial center of the spindle. By tilting, the posture of the probe can be optimized for measuring a complex work piece shape.
However, in the probe head rotation mechanism disclosed in Japanese Unexamined Patent Publication No. H03-504278, a motor main body (main body of a drive source) of a motor (drive source) modifying the posture of the probe is arranged on the axial center of the spindle. Therefore, thermal expansion of the motor due to heat generated when the motor is driven may directly lead to an error in a defined position of the probe.